The paper deals with the role of irony in the thought of Blaise Pascal. The author proposes to distinguish two types of irony in Pascal's work. The first type - offensive irony - can be found in The Provincial Letters, Pascal's polemics with the principles of Jesuit moral teachings. The use of ironie strategy allows Pascal to eriticize efficiently the Jesuit argumentation and the problematic consequences of their moral values. In Pascal' Pensées, the function of irony changes radically. Pascal's description of the position of human beings can be compared to the irony of situation, represented usually by The Oedipus King by Sophocles. Irony thus becomes a perspective which depicts the paradoxes of human existence and intensifies the emotional impact of Pascal's work.